Ten to 20 inches of rain, with local amounts of more than 2 feet, was dumped on southern Mississippi, southern Alabama and the Florida Panhandle. A 5-12 foot storm surge was measured along the northern Gulf Coast.

How unusual is this?

As it turned out, four simultaneous Atlantic hurricanes had not previously been observed in the satellite era; or since the 1960s.

Going back further into the so-called best-track database, there had been no record of four simultaneous Atlantic hurricanes since 1893.